Someone help me understand this. Wal-Mart sells a bike for $499 that is loaded with full 105 componentry, and PBK's lowest price is $609 for just the 105 group. I understand that the rest of the bike is probably crap ('cept maybe the brakes), but why would it not make sense to buy the WM bike to cannibalize and upgrade a lower-end CL bike?

Before the flame-fest begins, please bear in mind that I know how to work on bikes, I do support my LBS in ways other than buying bikes every year, and the bike at WM is likely assembled ass-backwards, requiring a reassemble anyway.